CA2789035A1 - Stator of a permanently excited rotating electric machine - Google Patents

Stator of a permanently excited rotating electric machine Download PDF

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Publication number
CA2789035A1
CA2789035A1 CA2789035A CA2789035A CA2789035A1 CA 2789035 A1 CA2789035 A1 CA 2789035A1 CA 2789035 A CA2789035 A CA 2789035A CA 2789035 A CA2789035 A CA 2789035A CA 2789035 A1 CA2789035 A1 CA 2789035A1
Authority
CA
Canada
Prior art keywords
teeth
stator
segment boundary
segment
segments
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
CA2789035A
Other languages
French (fr)
Inventor
Ulrich Hartmann
Axel Moehle
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of CA2789035A1 publication Critical patent/CA2789035A1/en
Abandoned legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K1/00Details of the magnetic circuit
    • H02K1/06Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12Stationary parts of the magnetic circuit
    • H02K1/16Stator cores with slots for windings
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K1/00Details of the magnetic circuit
    • H02K1/06Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/12Stationary parts of the magnetic circuit
    • H02K1/14Stator cores with salient poles
    • H02K1/146Stator cores with salient poles consisting of a generally annular yoke with salient poles
    • H02K1/148Sectional cores
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K29/00Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/03Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/18Structural association of electric generators with mechanical driving motors, e.g. with turbines
    • H02K7/1807Rotary generators
    • H02K7/1823Rotary generators structurally associated with turbines or similar engines
    • H02K7/183Rotary generators structurally associated with turbines or similar engines wherein the turbine is a wind turbine

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)
  • Permanent Magnet Type Synchronous Machine (AREA)

Abstract

The invention relates to a stator of a permanently excited rotating electric machine, wherein the stator comprises a plurality of segments disposed adjacent to one another in the circumferential direction of the stator, wherein the segments have teeth and grooves extending in the axial direction of the stator, wherein segments which immediately adjoin one another are in contact with one another at a segment boundary, wherein the teeth of the segments which immediately adjoin one another are disposed such that at the segment boundary one tooth of one segment is in contact with one tooth of the segment immediately adjoining the one segment, wherein the sum of the widths of the two teeth which are in contact at the respective segment boundary is greater than the uniform width of the majority of teeth which are not disposed immediately at a segment boundary, or of all teeth which are not disposed immediately at a segment boundary. The invention makes it possible to reduce detent moments and/or oscillating moments occurring in a permanently excited rotating electric machine.

Description

Description Stator of a permanently excited rotating electric machine The invention relates to a stator of a permanently excited rotating electric machine.

With a permanently excited rotating electric machine, such as for instance a permanently excited generator or a permanently excited electric motor, the detent moments are in particular a critical design variable during idling of the electric machine. The amplitude of the detent moments must be kept to a minimum here.
Furthermore, the oscillating moments which occur under load must also be kept to a minimum.

Particularly with directly driven, permanently excited wind power generators, the detent moments, which occur during idling, and the oscillating moments, which occur during operation of the wind power generator, are to be kept to a minimum.

The following methods are nowadays essentially used to minimize the oscillating moment:

= Slanting of the permanent magnets disposed in the rotor of the electric machine, = Slanting of the electrical conductor in the stator of the electric machine, = Displacement of the permanent magnets of the rotor from the pole axis.
The afore-cited known methods are however complicated in terms of manufacture.

It is the object of the invention to reduce detent and/or oscillating moments occurring in a permanently excited rotating electric machine.

This object is. achieved by a stator of a permanently excited rotating electric machine, wherein the stator has several segments disposed adjacent to one another in the peripheral direction of the stator, wherein the segments comprise teeth and grooves extending in the axial direction of the stator, wherein segments which are immediately adjacent to one another in each instance touch at a segment boundary, wherein the teeth of the segments immediately adjacent to one another are disposed such that a tooth of the one segment touches a tooth of the segment immediately adjacent to the one segment at the segment boundary, wherein the sum of the widths of the two teeth touching at the respective segment boundary is greater than the uniform width of the plurality of teeth which are not disposed immediately at a segment boundary or of all teeth which are not disposed immediately at a segment boundary.

Advantageous embodiments of the invention result from the dependent claims.

It has proven advantageous if the sum of the widths of the two teeth touching at the respective segment boundary'is smaller than or equal to twice the uniform width of the plurality of teeth, which are not disposed immediately at a segment boundary or of all teeth which are not disposed immediately at a segment boundary. If the widths of the two teeth touching at the respective segment boundary are in the specified range, the detent and/or oscillating moments are reduced particularly significantly.

It has also proven advantageous if a minimum number of the teeth, which are not disposed immediately adjacent at a segment boundary, has a uniform width which is greater than the uniform width of the plurality of teeth, which are not disposed immediately at a segment boundary. This measure further reduces the detent and/or oscillating moments.

It has also proven advantageous if the minimum number of teeth, which are not disposed immediately at a segment boundary, has a uniform width, which is smaller than or equal to twice the uniform width of the plurality of teeth which are not disposed immediately at a segment boundary. If the width of the minimum number of teeth which are not disposed immediately at a segment boundary has a uniform width which is in the specified range, the detent and/or oscillating moments are reduced particularly significantly.

Furthermore, it has proven advantageous if the widths of the two teeth touching at the respective segment boundary are of equal size, since the segments are then embodied to be particularly mechanically stable at the segment boundary.

The permanently excited rotating electric machine can in this way be embodied as a generator or electric motor for-instance, wherein the generator can be embodied in particular as a wind power generator and in particular as a directly driven (the wind wheel is directly connected to the wind power generator without interconnected gearing) wind power generator.

An exemplary embodiment of the invention is shown in the drawing and is explained in more detail below, in which:

FIG 1 shows a schematic view of an inventive permanently excited rotating electric machine and FIG 2 shows a schematic detailed view of a cutout of an inventive stator of the machine within the scope of an embodiment of the invention.

FIG 3 shows a schematic detailed view of a cutout of an inventive stator of the machine within the scope of a further embodiment of the invention.

FIG 1 shows an inventive permanently excited rotating electric machine 1 in the form of a schematic perspective representation.
The machine 1 is in this way embodied as a generator and in particular as a wind power generator within the scope of the exemplary embodiment. It should be noted at this point that for the sake of clarity, only the elements of the machine 1 which are essential to the understanding of the invention are shown in FIG
1.

The machine 1 comprises a rotor 2, which is disposed so as to be rotatable about an axis of rotation R of the machine 1. Here the rotor 2 includes all elements of the machine 1 which are disposed so as to be rotatable about the rotor axis R. The rotor 2 has a rotor yoke 3 on which permanent magnets are arranged, wherein for the sake of clarity, only a permanent magnet 4 is provided with a reference character in FIG 1. During operation of the machine 1, the rotor 2 rotates within the scope of the exemplary embodiment about a stator 5 disposed centrally in the machine 1 and at rest compared with the surroundings of the machine 1. Since the rotor 2 is disposed around the stator 5, such a machine is also referred to as external rotor in technical terms. Since the rotor 1 has permanent magnets, which permanently generate a magnetic field for operating the machine 1, such a machine is also referred to in technical terms as permanently excited or as a permanent magnet-excited machine. Since the machine 1 has a rotor 2 rotating about an axis of rotation R during operation of the machine 1, such a machine is also referred to as rotating electric machine.

The inventive stator 5 comprises several segments disposed adjacent to one another in the peripheral direction U of the stator 5. Within the scope of the exemplary embodiment, the stator 5 in this case has six segments, wherein for the sake of clarity only the segments 8a and 8b are provided with a reference character. The segments comprise teeth and grooves extending in the axial direction Z of the stator 5, wherein for the sake of clarity, only the teeth 7a, 12a, 7b, 12b and the groove 6 are provided with a reference character in FIG 1. In this way segments immediately adjacent to one another in each instance touch at a segment boundary, wherein for the sake of clarity only the segment boundary 9 at which the segments 8a and 8b touch is provided with a reference character. Each segment consists of metal sheets disposed one behind the other in the axial direction Z. The individual metal sheets of a segment are in this way generally provided with an electric insulation layer, such as for instance a lacquered layer. During assembly of the stator 5, the segments are disposed adjacent to one another in the peripheral direction U and connected to, one another resulting in the tubular stator 5 shown.

The teeth and grooves of the segments are produced by a corresponding molding ofthe form of the metal sheet. The electrical windings of the stator extend around the teeth into the grooves, wherein for the sake of clarity and since they are not essential to the understanding of the invention, the windings are not shown.

With commercially available permanently excited rotating electric machines, the widths of the individual teeth of the stator 5 are identical here. In accordance with the invention, detent and oscillating moments produced during operation of the machine 1 are reduced here by a target widening of specific teeth compared with the remaining teeth of the stator.

It should be noted again at this point that FIG 1 is a schematic representation in which for instance the width, number and dimensions of the teeth, grooves and permanent magnets, as well as the size of the air gap disposed between the stator and rotor do not correspond with the reality for instance.

FIG 2 shows a cutout of the segment 8a and of the segment 8b immediately adjacent to the segment 8a in the form of a schematic sectional view. The two segments 8a and 8b touch at the segment boundary 9. In the cutout shown, segment 8a has the teeth 12a, 7a, 7a', 7a'' and 7a''' and segment 8b has the teeth 12b, 7b, 7b', 7b'' and 7b'''. It should be noted at this point that in reality a segment can have hundreds of teeth and grooves for instance, so that only a small cutout of the segments is shown in FIG 2.

In accordance with the invention, the teeth of the segments immediately adjacent to one another are disposed such that a tooth of the one segment touches a tooth of the segment immediately adjacent to the segment at the respective segment boundary. Within the scope of the exemplary embodiment, the teeth of the segments 8a and 8b disposed immediately adjacent to one another are disposed such that a tooth of the one segment 8a touches a tooth of the segment 8b immediately adjacent to the segment 8a at the segment boundary 9 in each instance. Within the scope of the exemplary embodiment, these are the teeth 12a and 12b which touch one another at the segment boundary 9. No division of the stator therefore takes place within a groove in accordance with the invention.

For the sake of clarity, only a groove 6 is provided with a reference character in FIG 2. A segment, as already mentioned, does not end in the peripheral direction U at a groove, i.e. the segment boundary 9 does not lie within a groove. The tooth 12a has a width a and the tooth 12b has a width b. The teeth, which are not disposed immediately adjacent to a segment boundary, i.e.
in the exemplary embodiment according to FIG 2, the teeth 7a, 7a', 7a'', 7a''', 7b, 7b' 7b'' and 7b''' shown, have a uniform width c, i.e. they are all the same width. In accordance with the invention, the sum (a+b) of the widths a and b, of the teeth 12a, 12b touching at the respective segment boundary is greater than the uniform width c of all teeth (7a, 7a', 7a'', 7a''', 7b, 7b', 7b'', 7b '' '), which are not disposed immediately at a segment boundary 9.

In other words the following applies a+b > c The overall tooth 11 formed from both teeth 12a and 12b touching at the segment boundary 9 therefore has a larger width, in particular significantly larger width than the uniform width c of the teeth which are not disposed immediately at a segment boundary 9. The detent and oscillating moments are significantly reduced by the inventive measure. Contrary to the prior art, no arbitrary tooth is therefore divided by the segment boundary so that the partial teeth thus developing, such as in the prior art, by disregarding a minimum air gap possibly developing between the two sub teeth, are not as wide as an undivided tooth.

The sum (a+b) of the widths a, b of the two teeth 12a and 12b touching at the respective segment boundary is preferably embodied to be smaller than or equal to twice the uniform width c of all teeth, which are not disposed immediately at a segment boundary, i.e the following applies c < a+b << 2c If the sum (a+b) of the widths a, b is selected in this range, the detent and oscillating moments are reduced particularly significantly.

A high mechanical stability of the segments is achieved if the widths a and b of the two teeth touching at the respective segment boundary are of equal size, i.e. a=b applies.

Within the scope of a uniform production, it is advantageous here if all teeth of a segment and thus of the stator have a uniform width, i.e. the following applies:

a = b = c This measure also achieves a particularly high mechanical stability of the stator and of the individual segments, since no teeth are present at the segment boundary, which only still comprise part of the width of the teeth, which are not disposed at the segment boundary.

FIG 3 shows a further embodiment of the invention, wherein in FIG
3 identical elements are provided with identical reference characters as in FIG 2. The embodiment according to FIG 3 corresponds to the embodiment according to FIG 2 in terms of function and design, wherein with the embodiment according to FIG
3, a minimum number of teeth, which are not disposed immediately -at the segment boundary, have a larger width than the uniform width of the plurality of teeth which are not disposed immediately at a segment boundary. Within the scope of the exemplary embodiment, the teeth 13a and 13b herewith have a width b which is greater than the uniform width c of the plurality of teeth 7a, 7a', 7a'', 7b, 7b', 7b'', which are not disposed immediately at a segment boundary, in other words the following applies:

d > c The sum (a+b) of the widths a and b of the two teeth touching at the respective segment boundary 9 is greater in this case than the uniform width c of the plurality 7a, 7a', 7a", 7b, 7b', 7b"
which are not disposed immediately at a segment boundary.

A particularly good suppression of detent and oscillating moments is achieved if the minimum number of teeth (13a, 13b), which are not disposed immediately at a segment boundary, have a uniform width b, which is smaller than or equal to twice the uniform width c of the plurality of teeth which are not disposed immediately at a segment boundary, i.e. the following applies:

c < d << 2c It is naturally also advantageous in this embodiment of the invention for the widths of the two teeth touching at the respective segment boundary to be of equal size, i.e. the following applies:

a = b In order to achieve particularly high stability, it may preferably also apply to the width of the teeth:

a = b = c i.e., the width of the teeth, which are disposed immediately at a segment boundary, corresponds to the width of the plurality of teeth, which are not disposed immediately at a segment boundary.

The statements made above within the scope of the description relating to FIG 2 and FIG 3 in respect of the two segments 8a and 8b also apply accordingly to the remaining segments of the stator which are not shown in FIG 2 and FIG 3.

Complicated measures such as pole offset or groove slanting can, in manufacturing terms, be dispensed with using the invention.
On account of the higher rigidity and on account of the tooth arranged at the segment boundary, the thus embodied segments are simpler to manufacture and to assemble than with a commercially available stator, in which all teeth including the overall tooth formed from the two teeth touching at the respective segment boundary have a uniform width (a + b = c = d).

Claims (7)

1. A stator of a permanently excited rotating electric machine (1), wherein the stator (5) comprises several segments (8a, 8b) disposed adjacent to one another in the peripheral direction (U) of the stator (5), wherein the segments (8a, 8b) comprise teeth (7a, 7a', 7a", 7a"', 7b, 7b', 7b", 7b"', 13a, 13b, 12a, 12b) extending in the axial direction (Z) of the stator (5) and grooves (6), wherein segments (8a, 8b) immediately adjacent to one another in each instance touch at a segment boundary (9), wherein the teeth (7a, 7a', 7a", 7a"', 7b, 7b', 7b", 7b"', 13a, 13b, 12a, 12b) of the segments (8a, 8b) disposed immediately adjacent to one another such that a tooth (12a) of the one segment (8a) touches a tooth (12b) of the segment (8b) immediately adjacent to the one segment (8a) in each instance at the segment boundary (9), wherein the sum of the widths (a, b) of the two teeth (12a, 12b) touching at the respective segment boundary (9) is greater than the uniform width (c) of the plurality of teeth (7a, 7a', 7a", 7b, 7b', 7b"), which are not arranged immediately at a segment boundary (9) or of all teeth 7a, 7a', 7a", 7a"', 7b, 7b', 7b", 7b"') which are not disposed immediately at a segment boundary (9).
2. The stator as claimed in claim 1, characterized in that the sum of the widths (a, b) of the two teeth (12a, 12b) touching at the respective segment boundary (9) is smaller than or equal to twice the uniform width (c) of the plurality of teeth (7a, 7a', 7a", 7b, 7b', 7b"), which are not arranged immediately at a segment boundary (9) or of all teeth (7a, 7a', 7a", 7a"', 7b, 7b', 7b", 7b"') which are not arranged immediately at a segment boundary (9).
3. The stator as claimed in one of the preceding claims, characterized in that a minimum number of teeth (13a, 13b), which is not disposed immediately at a segment boundary (9), has a uniform width (d) which is greater than the uniform width (c) of the plurality of teeth (7a, 7a', 7a", 7b, 7b', 7b") which are not arranged immediately at a segment boundary (9).
4. The stator as claimed in claim 3, characterized in that the minimum number of teeth (13a, 13b) which are not disposed immediately at a segment boundary (9), have a uniform width (d) which is smaller than or equal to twice the uniform width (c) of the plurality of teeth (7a, 7a', 7a", 7b, 7b', 7b"), which are not disposed immediately at a segment boundary (9).
5. The stator as claimed in one of the preceding claims, characterized in that the widths (a, b) of the two teeth (12a, 12b) touching one another at the respective segment boundary (9) are of equal size.
6. A permanently excited rotating electric machine (1), wherein the machine (1) is embodied as a generator or electric motor and comprises a stator (5) as claimed in one of the preceding claims.
7. The permanently excited rotating electric machine (1) as claimed in claim 6, characterized in that the generator is embodied as a wind power generator.
CA2789035A 2010-02-05 2010-12-30 Stator of a permanently excited rotating electric machine Abandoned CA2789035A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102010001620A DE102010001620A1 (en) 2010-02-05 2010-02-05 Stand of a permanent magnet rotating electrical machine
DE102010001620.9 2010-02-05
PCT/EP2010/070911 WO2011095264A2 (en) 2010-02-05 2010-12-30 Stator of a permanently excited rotating electric machine

Publications (1)

Publication Number Publication Date
CA2789035A1 true CA2789035A1 (en) 2011-08-11

Family

ID=44316370

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2789035A Abandoned CA2789035A1 (en) 2010-02-05 2010-12-30 Stator of a permanently excited rotating electric machine

Country Status (9)

Country Link
US (1) US20120299434A1 (en)
EP (1) EP2532073B1 (en)
BR (1) BR112012019359A2 (en)
CA (1) CA2789035A1 (en)
DE (1) DE102010001620A1 (en)
DK (1) DK2532073T3 (en)
ES (1) ES2454840T3 (en)
RU (1) RU2516367C2 (en)
WO (1) WO2011095264A2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2922177A1 (en) * 2014-03-19 2015-09-23 Siemens Aktiengesellschaft Stator segment with asymmetrical half tooth shape for large generators
EP2924847A1 (en) 2014-03-28 2015-09-30 Siemens Aktiengesellschaft Composite electric machine
EP2930825A1 (en) 2014-04-11 2015-10-14 Siemens Aktiengesellschaft Mounting of permanent magnets on a rotor of an electric machine
EP3780340A1 (en) * 2019-08-14 2021-02-17 Siemens Gamesa Renewable Energy A/S Segmented stator for a generator, in particular for a wind turbine

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1779950A (en) * 1927-06-29 1930-10-28 Siemens Ag Body constructed of sheet-iron sections
AT133333B (en) 1928-11-10 1933-05-10 Siemens Ag Magnetic frame for direct current machines.
SU955368A1 (en) * 1981-01-08 1982-08-30 Ленинградское Электромашиностроительное Объединение "Электросила" Им.С.М.Кирова Synchronous electric machine stator
US4700098A (en) 1984-12-28 1987-10-13 Sanyo Electric Co., Ltd. D.C. motors with unequal pole spacing
SU1599938A1 (en) * 1988-02-10 1990-10-15 Институт Электродинамики Ан Усср Electric machine stator
SU1677782A1 (en) * 1988-12-20 1991-09-15 Предприятие П/Я Г-4993 Stator of electrical machine
JP2538134B2 (en) * 1991-04-08 1996-09-25 田辺製薬株式会社 Sustained release preparation and method for producing the same
US6321439B1 (en) * 1997-01-21 2001-11-27 Siemens Westinghouse Power Corporation Method for assembly of a stator in the field
US7915751B2 (en) * 2008-06-03 2011-03-29 Institute Of Nuclear Energy Research Output power control of a wind power generator through bendable tail wing and tail rod
CN201298796Y (en) * 2008-08-18 2009-08-26 于波 Direct drive compositely excited wind energy generator

Also Published As

Publication number Publication date
US20120299434A1 (en) 2012-11-29
EP2532073A2 (en) 2012-12-12
DE102010001620A1 (en) 2011-08-11
BR112012019359A2 (en) 2018-05-08
WO2011095264A3 (en) 2012-08-16
DK2532073T3 (en) 2014-06-02
RU2516367C2 (en) 2014-05-20
WO2011095264A2 (en) 2011-08-11
RU2012137714A (en) 2014-03-10
EP2532073B1 (en) 2014-03-19
ES2454840T3 (en) 2014-04-11

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EEER Examination request
FZDE Discontinued

Effective date: 20151113